/*
 * Copyright (c) 2010, okazoh_tk. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *  - Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *  - Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *  - Neither the name of the copyright holder nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef ALKES_TEXTEND_BUFFER_H_INCLUDED_
#define ALKES_TEXTEND_BUFFER_H_INCLUDED_

#include "alkes/internal.h"
#include "alkes/core/MemoryExtendPolicy.h"

namespace alkes {

#ifndef AL_DEFAULT_EXTEND_POLICY
#define AL_DEFAULT_EXTEND_POLICY alkes::NoCopyExtendPolicy<alkes::StdlibAllocator>
#endif

template<class ExtendPolicy = AL_DEFAULT_EXTEND_POLICY >
class TExtendBuffer
{
public:
    TExtendBuffer();
    ~TExtendBuffer();

    void* getBuffer(uint32_t request_size);
    const void* pointer() const { return buffer_; }

private:
    uint32_t buffer_size_;
    void* buffer_;
};

template<class ExtendPolicy>
TExtendBuffer<ExtendPolicy>::TExtendBuffer()
: buffer_size_(0)
, buffer_(0)
{
}

template<class ExtendPolicy>
TExtendBuffer<ExtendPolicy>::~TExtendBuffer()
{
    if (buffer_)
    {
        ExtendPolicy::allocator_type::deallocate(buffer_);
    }
}

template<class ExtendPolicy>
void* TExtendBuffer<ExtendPolicy>::getBuffer(uint32_t request_size)
{
    buffer_ = ExtendPolicy::extend(buffer_, buffer_size_, request_size);
    return buffer_;
}

template class AL_EXPORT TExtendBuffer< NoCopyExtendPolicy<alkes::StdlibAllocator> >;
template class AL_EXPORT TExtendBuffer< CopyExtendPolicy<alkes::StdlibAllocator> >;

}

#endif
